Virtualization & Containers Archives • Helge Klein

Docker (Compose) Cheat Sheet

This is a collection of tips and tricks I picked up while learning and working with Docker and Docker Compose on my home server and web server.

Windows Server 2019 on Hetzner’s EX62 & AX100 Dedicated Servers

This post is a follow-up to my 2016 article on how to install Windows Server on Hetzner’s EX51 hosted dedicated servers. Hetzner offers many types of dedicated servers at very attractive prices and – astonishingly – good support. This article lists some issues we encountered while installing Windows Server 2019 on the EX62 and AX100 […]

Inexpensive GPU Virtualization Options for Testing

For a new chapter in my ongoing series of talks and articles about browser performance I wanted to examine how key user experience metrics like page load time are dependent on available hardware resources. I prepared a VM and started my tests with a single CPU core and 2 GB of RAM, planning to gradually […]

Hyper-V Backup – Products & Options

It’s 2018, and backing up Hyper-V hosts is solved, right? I certainly expected it to be when I took on the task of finding a simple and reliable way to back up three hosts colocated in a large datacenter. This article summarizes my journey and the findings resulting from it.

Faster Trimming & Compacting of Hyper-V Ubuntu VMs

A while ago I described how to compact an Ubuntu VHDX running on Hyper-V using the sfill command. Running sfill, however, can take hours. Luckily, there is a much faster alternative. Ubuntu Trim and Hyper-V Ubuntu running in a Hyper-V virtual machine has been supporting the trim command since version 14.04 (details). The OS issues […]

Hyper-V on Hetzner’s EX51 Hosted Dedicated Servers

Your low-cost high-performance cloud data center building block. This guide explains how to install Windows Server 2012 R2 on Hetzner’s EX51-SSD dedicated servers. That line of servers is very attractive for virtualization as it combines a fast CPU with a good amount of RAM and SSD storage – at a price point of less than […]

Compacting Hyper-V VHDX Files of Ubuntu Linux VMs

Note: if your guest OS supports the trim command you can use the faster method described in this article. If you configured your Hyper-V virtual machines with dynamically expanding virtual disks you will find that the VHDX files backing the virtual disks always grow in size, they never shrink. Eventually this becomes a problem either […]

Compacting Client Hyper-V VHDX Files

Virtual hard disks have the same tendency to grow in size as regular disks have to fill up. Deduplication is a great way to battle this, but unfortunately it is not available for Windows 8 Client Hyper-V. I know that hacks are available describing how to transfer the relevant DLLs from Server 2012 but I […]

My Hyper-V Server in the Cloud

There are many possible reasons for wanting a fast server well connected to the internet. Some may want to move their lab from their powerful but heavy laptop to the cloud so they only need to carry around a lightweight ultrabook. Others may want to set up a demonstration system for their software or solutions […]

Windows 8 Client Hyper-V: Internet Access Without 2nd NIC

Having a hypervisor built right into the client operating system is a great thing, especially if it is as fast and stable as Client Hyper-V found in Windows 8. The functionality is very good, too, but a single feature is sorely missing: the ability to share the host’s (internet) network connection.

The Effects of HP’s Power Profile on vCPU Performance

When you buy a new HP server it comes with the BIOS setting HP Power Profile set to Balanced Power and Performance. That sounds good but is bad – at least for CPU performance in a VDI environment.

Installing ESXi 4.1 on HP DL380 G8: No NICs Found

This kept us occupied quite a bit: after having worked with HP’s G7 line of servers for a long time, we ordered our first DL380 G8 for use with VDI. According to HP’s documentation the same custom image can (and must be) used when installing ESXi as with the G7. With that information, setting up […]

Removing “Eject VMware Virtual disk SCSI Disk Device”

The HotPlug functionality of VMware ESX(i) 4 and 5 has the negative side effect that it is easily possible to “eject” hardware devices from inside the virtual machine, completely removing the respective device from the VM configuration. This is especially bad if it happens to the network card, and others have already described how to […]

Will We Use Cloud-Based Virtual Desktops in 2020?

A desktop delivered from the cloud, accessible from everywhere, providing just the right amount of computing power for the task at hand, maintained by the cloud provider and paid for only when used – a dream? Or a commodity in ten years’ time? Time will tell, but in the meantime let us find out if […]

Virtualization – Old Hat?

Although humans in general and members of its subspecies “marketing manager” in particular tend to treat currently “hot” topics as new and revolutionary, they only rarely are. In fact, “new” should be considered as in “new wine in old bottles” rather than in “did not exist before”. Take virtualization. Although the topic of the day […]

Virtualization? Nothing But Lies!

With virtualization, lying has become respectable. Processors lie to user mode processes about memory addresses. Computers lie to operating systems about installed hardware. Storage systems lie to everybody about the location of data. The virtualization hype transforms honest down-to-earth systems into lying medusas.

Is VMware Clustering / VMotion Complex Compared to Microsoft Failover Clustering?

My last post on VMware VMotion urged several readers to protest, maybe because of its provocative title. What I did was to compare VMware clustering with Microsoft failover clustering. I got to the conclusion that both significantly add to the complexity of the environment. Interestingly, most commenters said, yes, Microsoft clustering is complex, but no, […]

VMotion Is Hyped by Consultants, But Do Admins Even Use It?

Some time ago I attended a presentation by a former VMware, now Microsoft employee who claimed that Hyper-V’s lack of Live Migration aka VMotion is not relevant at all. According to him, the only people vigorously demanding such a feature are consultants, never customers. At the time I thought: “What a silly marketing number this […]

VMware vs. Microsoft: Why Memory Overcommitment is Useful in Production and Why Microsoft Denies it

In the ongoing virtualization war much has been written (pro and con) about the value of memory overcommitment, a feature VMware ESX has and Microsoft Hyper-V is lacking (XenServer, too, for that matter). But only few people take a look at what the term overcommitment actually means. In this article I will explain how overcommitment […]

Category: Virtualization & Containers

Docker (Compose) Cheat Sheet

Windows Server 2019 on Hetzner’s EX62 & AX100 Dedicated Servers

Inexpensive GPU Virtualization Options for Testing

Hyper-V Backup – Products & Options

Faster Trimming & Compacting of Hyper-V Ubuntu VMs

Hyper-V on Hetzner’s EX51 Hosted Dedicated Servers

Compacting Hyper-V VHDX Files of Ubuntu Linux VMs

Compacting Client Hyper-V VHDX Files

My Hyper-V Server in the Cloud

Windows 8 Client Hyper-V: Internet Access Without 2nd NIC

The Effects of HP’s Power Profile on vCPU Performance

Installing ESXi 4.1 on HP DL380 G8: No NICs Found

Removing “Eject VMware Virtual disk SCSI Disk Device”

Will We Use Cloud-Based Virtual Desktops in 2020?

Virtualization – Old Hat?

Virtualization? Nothing But Lies!

Is VMware Clustering / VMotion Complex Compared to Microsoft Failover Clustering?

VMotion Is Hyped by Consultants, But Do Admins Even Use It?

VMware vs. Microsoft: Why Memory Overcommitment is Useful in Production and Why Microsoft Denies it